A gas turbine engine includes a fan section, a compressor section, a combustor section, and a turbine section. The fan section drives air along a bypass flowpath while the compressor section drives air along a core flowpath for compression and communication into the combustor section then expansion through the turbine section
The engine typically includes a low speed shaft and a high speed shaft mounted for rotation about an engine central longitudinal axis relative to an engine static structure via several bearing systems. The high speed shaft interconnects a high pressure compressor and high pressure turbine. The low speed shaft interconnects a fan, a low pressure compressor, and a low pressure turbine. In one example, the low speed shaft is connected to the fan through a geared architecture to drive the fan at a lower speed than the low speed shaft. The low pressure compressor is positioned aft or rearward of the geared architecture. An example engine configuration having this low pressure compressor position is found in U.S. Pat. No. 8,176,725.
The core airflow is compressed by the low pressure compressor then the high pressure compressor, mixed and burned with fuel in a combustor, then expanded over the high pressure turbine and low pressure turbine. The turbines rotationally drive the respective low speed and high speed shafts in response to the expansion. This typical arrangement provides a geared turbofan of significant length. In certain applications shorter engine lengths are needed.